Fastener inserting devices



Sept.9, 1958 w. M. HOUGHTON .FASTENER INSERTING DEVICES 4 Sheets-Sheet 1Filed July 26, 1956 m w y {w i mM w Vz W .IWB. m 1 k M 0 0 fl w 5 $2 2w, H W a H F A W w .6 0 p} .m M A g//k la f! W. M. HOUGHTON FASTENERINSERTING DEVICES Sept; 9; 1958 4 Sheets-Sheet 2 Filed July 26, 1956Inventor William MHoug/norz P 9, 1953 w. M. HOUGHTON 2,850,736 FASTENERINSERTING DEVICES Filed July 26, 1956 4 Sheets-Sheet 5 t InventorW'Zliam M Houghfon B e5 Sept. 9, 1958 Filed July 26, 1956 W. M. HOUGHTONFASTENER INSERTING DEVICES 4 Sh eets-Sh eet 4 Inventor W/z'lliam .MHoughzon By his z I 2 e3 United States Patent FASTENER INSERTING DEVICES.

William M. Houghton, Marblehead, Mass., assignor to United ShoeMachinery Corporation, Flemington, N. J., a corporation of New JerseyApplication July 26, 1956, Serial No. 600,326

Claims. (Cl. 1-1) anism which automatically orients and feeds fastenersone at a time upon receipt of a signal emanating from the tool.Generally, there are three lines or conduits attached to the drivingtool. The first is a fiuid supply line, and since these tools areusually operated by compressed air, the supply line is an airtightconduit. The second line is a fastener delivery tube through whichfasteners are propelled from the feeding mechanism and the third is asignal line to transmit a pneumatic signal to the feeding mechanism todeliver a fastener. dom of movement of the driving tool are importantfactors influencing operator fatigue and consequently his production,thus an obvious advantage results from reducing the weight andincreasing freedom of movement by eliminating one or more of the linesattached to the tool.

An object, therefore, of this invention is to provide a fastenerinserting device having a light weight portable driving tool with aminimum of separate lines or conduits attached thereto.

Attempts have been made to combine the air supply line and the fastenerdelivery tube in a single conduit but this requires complex valvemechanism on the driving tool which adds to, rather than subtracts from,its weight. However, since the signal line must also be connected to thedriving tool by an appropriate valve, the elimination of the signal lineobviates the necessity for this valve and thereby not only reduces theweight of the tool but its cost as well.

Another object of this invention, therefore, is to provide afluid-operated fastener inserting device having an automatic feedingmechanism and a portable driving tool which device does not require aseparate signal line connecting the driving tool to the feedingmechanism.

Because the rate of operation of thedriving tool is determined for themost part by the nature of the work, the rate of fastener consumption isnot always constant but more often is irregular or intermittent. Thus,the feeding rate cannot be maintained constant but must be responsive tothe requirements of the tool, otherwise a fastener could reach the toolbefore the preceding one has been inserted and jamming might result.However, to assure that no unnecessary delay takes place between drivingcycles, the feeding mechanism should be actuated in timed sequence withthe operation of the driving tool, and preferably in immediate responsethereto.

Accordingly, it is still another object of this invention to provide afastener inserting device having a feeding mechanism connected to aremote portable driving tool which device does not require a separatesignal line but which has means for detecting accurately each drivingcycle and for actuating the feeding mechanism to feed a fastener inimmediate response thereto.

Some of the more frequently used driving tools of the Theweight andfree- I M 2,850,736 Patented Sept. 9, 1958 portable pneumatic type aresingle or multiple blow nail drivers and rotary screw drivers, etc.,whichvare connected by means of supply lines to substantially constantpressure sources of compressed air, such as, large capacity storagetanks or factory air systems. Each time one of these tools is operatedto insert a fastener it consumes a quantity of compressed air resultingin a flow of air through the supply line. Applicant has found that bythe use of appropriate flow detection mechanism in the supply line it ispossible to determine with extreme accuracy when the driving operationof the driving tool begins and when it ceases. Furthermore, bytriggering the feeding mechanism by the flow detection mechanism afastener may be delivered in response to the operation of the drivingtool without the need for a separate signal line.

In accordance with the above objects and as a feature of this inventionthere is provided a fluid operated fastener inserting device having alight weight portable driving tool-connected to a remotely locatedfeeding mechanism with a flow responsive valve positioned in a linewhich supplies compressed fluid to operate the driving tool, the valvebeing operable to detect fluid flow in the line caused by the operationof the tool, and in response thereto, toactuate the feeding mechanism tosupply a fastener to the driving tool.

The above and other features of the invention including various noveldetails of construction and combination'of parts will now be moreparticularly described with reference to the accompanying drawings andpointed out in the claims.

In the drawings,

Fig. 1 is a side elevation of a device embodying the invention foraligning fasteners with respect to their ends and for feeding them oneat a time under pressure through a delivery conduit to a remotelylocated portable driving tool;

Fig. 2 is a vertical section through a flow responsive valve used toactuate the feeding mechanism shown in Fig. 1; i

Fig. 3 is a plan view partly in section of a portion ofthe feedingmechanism shown in Fi 1 for separating a singlefastener, transferring itto a delivery conduit and propelling it therethrough; under pressure. tothe in-v serting tool;

Fig. 4 is a side elevation partly in section of the mech: anism shown inFig. 3; and

Figs. 5 and 6 are diagrammatical views of the device shown in Fig. 1including its pneumatic circuit, Fig.5 showing the apparatus as employedwith a single-blow nail driving gun and Fig.6 showing it as employedwith a rotary screw driver.

Applicants flow responsive valve may be used incombination with anypneumatically operated fastener feeding mechanism and driving tool. Byway of example only, it is herein illustrated in combination with atotally pneumatic type fastener separating and feeding mechanismidentical to that disclosed in an application for United States LettersPatent Serial No. 550,324, filed December- 1, 1955 in the name of DonaldB. Mcllvin et al. The McIlvin device, hereinafter referred to also asthe feeder.- separator, is best seen in Fig. 1 and comprises a hopper.

10 for holding a supply of randomly orientedfasteners,

such as nails or screws. The hopper is secured to a main frame 12 whichmay be mounted on a bench or other suitable support. Forming one side ofthe hopper,

is an elevating mechanism for, lifting fasteners :from the hopper anddelivering them to a downwardly inclined, slotted raceway 14 along whichthe fasteners slide in uniformly alined relationship suspended by theirheads, The elevating mechanism comprises. a plurality of liftslides 16connected by a piston rod,18. to an air motor 11! which is controlled bya valve 22 for reciprocating the slides. Associated with the raceway 14,which is adjustable widthwise to accommodate various types and sizes offasteners, is a rotary rejector 24 to expel any misalined fasteners fromthe raceway. Secured to the frame 12 and mounted on the lower end of thedownwardly inclined raceway 14 is a separating and feeding element 34which separates the endmost fastener from those in the raceway and feedsit under pressure through a delivery tube 36 to a driving tool, such asa pneumatic nail or screw driving gun, not shown in Fig. 1. Theseparating and feeding element 34 is pneumatically operated, beingconnected to the same source of pressurized air as are the driving tooland the motor 20 which operates the lift slides 16. A flow responsivecontrol valve 38 is mounted on the frame 12 in any convenient positionand is connected to the feeding and separating element 34 and thedriving tool as shown in Figs. and 6 as described in detail hereinafter.

The flow responsive valve 38 is best seen in Fig. 2 and has a valvecasing 40 of irregular configuration which forms a valve chamber. In oneend of the casing 40 is a cylinder 42 in which slides a piston 44. Thepiston normally is urged byacompression spring 46 to a first positionagainst an internal shoulder 48 formed in the casing 40. The spring 46fits within an annular recess 50 in the piston 44 and around a collar 52formed on a plug 54 which is secured to the casing 40 by screws 55, onlyone of which is seen in Fig. 2. The plug 54 forms an airtight seal onone end of the cylinder 42. On the end of the piston 44 remote from theplug 54 there is an annular chamfered area 56. Extending lengthwisethrough the piston 44 are a small diameter or restricted passageway 58and the stem 59 of a control valve having the form of a spool valve 60.The valve 60 is movable relative to the piston 44 and is urged to theleft relative to the piston, as seen in Fig. 2, by means of a lightspring 62 compressed between the piston and a collar 64 fixed to thestem 59. In the upper portion of the casing 40 is threaded an air inletfitting 66 to provide an inlet opening from an air supply line 68 to amain chamber 70 forming part of the valve chamber within the casing 40.The main chamber 70 communicates with the open end of the cylinder 42and by means of the restricted passageway 58, with a chamber 72comprising the closed end of the cylinder 42 which is the portion of thecylinder located on the left-hand side of the piston 44. Threaded in alower part of the casing 40 is a fitting 74 to provide an exit openingbetween an air line 76 and an exit chamber 78 which communicates withthe chamber 72 of the cylinder 42 by means of interconnecting smalldiameter passageways 80 and 82 formed in the casing 40 and the plug 54respectively. A port 84 connects the chamber 78 directly with thecylinder 42.

The spool valve 60 comprises the above-mentioned stem 59, a flange 85and a pair of spools 86 and 88. The spools 86 and 88 are provided with 0rings of conventional type to form airtight seals with a cylinder 90 inwhich the valve 60 is slidable. One end of the cylinder 90 communicatesdirectly with the main chamber 70 and the opposite end communicates witha passageway 92 connected to the main chamber 70. Enclosing therighthand end of the cylinder 90 and the passageway 92 is a cap 94secured to the casing 40 by screws 96, only one of which is seen in Fig.2. Threaded in the casing 40 is a fitting 98 to provide a connectionbetween an air line 100 and a passageway 102 which is a secondary exitopening communicating with the cylinder 90. Also threaded in the casing40 is still another fitting 104 forming a connection between an air line106 and a chamber 108 which communicates with the cylinder 90 by meansof a passageway 110. The passageway 110, which may be considered anothersecondary exit opening, bypasses anddoes not communicate directly withthe passage- W91 The flow responsive valve 38 operates in the followingmanner. The air supply line 68 is connected to a substantially constantpressure source of compressed air, thus pressurizing the main chamber 70by means of the air inlet 66 and the chamber 72 by way of the smalldiameter or restricted passageway 58 in the piston 44. By means of thepassageway 82, the passageway 80, the exit chamber 78, and the air exitfitting 77, the air line 76 is also pressurized. The air line 76 isconnected to any device which is to consume compressed air. When thereis no flow of air through the line 76, the chamber 72 is maintained atthe same pressure as the main chamber 70 and the piston 44 is maintainedin its first position against the shoulder 48 by the spring 46. When airis drawn from the line 76, flow takes place through this line as well asthrough the exit chamber 78 and the passageways and 82. The passageway58 is sufliciently small to restrict the flow of air to the chamber 72to a quantity less than that which flows from the exit chamber 78through the line 76, resulting in an immediate small pressure drop inthe chambers 72 and 78. The greater air pressure then in the chamber 70,acting on the righthand face of the piston 44, causes it to be displacedto the left to a second position compressing the spring 46 and movingthe valve 60 to the left therewith.

The movement of the piston 44 to the second position uncovers the port84 leading to the exit chamber 78 whereby air then flows directly fromthe chamber 70 into the exit chamber 78 and the line 76. The port 84 incooperation with the piston 44 acts as a control or throttling valvewhich in cooperation with the force of the spring 46 maintains thepressure in the exit chamber 78 lower than the pressure in the mainchamber 70 during flow through the line 76. Fluctuations in flow throughthe line 76 caused, for example, by an increase or decrease in the rateof operation of the driving tool will result in fluctuations in pressurein the exit chamber 78. If the pressure in the exit chamber 78 decreasesslightly because of a greater flow, more of the port 84 will be exposedby the piston 44 since the lowered pressure also in the chamber 72 willpermit the pressure within the main chamber 70 'to displace the piston44 a somewhat greater amount to the left. Conversely, a small increasein pressure in the line 76 and thus in the exit chamber 78 caused byless flow will effect a throttling action, to wit, a slight movement ofthe piston 44 to the right making the effective size of the port 84somewhat smaller. Thus, the piston 44 may tend to float varying the sizeof the port 84 maintaining the pressure within the chamber 78 lower thanthe pressure in the chamber 70 during flow through the line 76.

In order to prevent any floating or oscillating motion of the piston 44from being transmitted to the valve 60, the piston is movable, within alimited range relative to thevalve. The above-mentioned 0 rings in thespools 86 and 88 maintain a sufiiciently close fit with the cylinder toprevent the valve 60 from moving as a result of slight movement of thepiston 44. Any floating or oscillating motion of the piston 44 causesthe spring 62 to become compressed or expanded to a greater or lesserdegree but the force of the spring 62 alone is insutficient to move thevalve 60 relative to the cylinder 90. Thevalve friction does not impedethe floating action of the piston 44.

The initial displacement of the piston 44 to the left, to the secondposition as stated above, moves the valve 60 to the left, the pistonabutting the collar 64 on the valve. This movement positions the spool88 to the left of thc secondary exit opening 102 placing the line incommunication with the pressurized passageway 92 to permit air to flowthrough the line 100 for purposes. such as actuating a feeder-separator,as hereinafter to be described.

When the flow through the line 76 stops, the chambers 78 and 72 againbecome pressurized at the same pressure its right-hand position againstthe shoulder 48 by the spring 46. The valve 60 is moved to the right bythe piston 44 engaging the collar 85, the spool 88 shutting off the line100 from the pressurized passageway 92-and placing the line 100 incommunication with the line 106 through the passageway 162, the cylinder90, the secondary exit opening 110 and the chamber 108. Whether the line106 is employed or the chamber 108 closed by a plug is determined by theuse to which the flow responsive valve 38 is placed as will become moreevident hereinafter.

The separating and feeding element 34 will now be described briefly. Fora more detailed explanation of its structure and operation theabove-mentioned Mcllvin application may be referred to. Referring toFig. 4, there is provided a presser foot 120 of rubber or similarmaterial arranged to be moved toward and away from the lower end of theraceway 14 to engage and then release the heads of fasteners, hereinillustrated as screws, as they slide down the raceway. The presser foot120 is urged downwardly toward the raceway by means of a spring 122 andis movable away from the raceway by an air operated piston 124 mountedwithin a cylinder 126. The air for elevating the piston 124 and hencethe presser foot 120 is supplied through a conduit 128 attached to afittting 129 threaded in the cylinder 126. As seen in Fig. 4, the lowerend of the raceway 14, all of which slopes downwardly (see Fig. 1), isfurther sloped along a portion 130 substantially parallel to the bottomof the presser foot 120'. The portion 130 terminates abruptly exposing afastener receiving area 132 extending beyond the presser footand spacedslightly below the portion 130. When the presser foot is elevated, theendmost fastener is released onto the receiving area 132, its shankengaging the closed wall of a sleeve 134 which is rotatably mountedwithin a housing 136. The'lower end of the sleeve is attached to theflexible delivery conduit 36 for conducting fasteners to the insertingtool. Rotary motion is imparted to the sleeve 134 by means of a slidablerack 140 (Fig. 3) which engages a pinion 142 secured to the top of thesleeve 134. In one position of rotation a slot 144 in the sleeve 134faces the receiving area 132 and in another position of rotation faces afitting 146 (Fig. 4) threaded into the housing 136 and connected to anair line 150. The rack 140 is attached to a piston 152 slidable within acylinder 154 which forms the upper portion of the housing 136. On oneend of the piston 152 is a head 156 and on the opposite end is a head158 separated from the main portion of the piston by a necked area 160.A cap 161 closes one end of the cylinder 154 and an air inlet fitting162 is threaded in a cap 164 secured to the opposite end of the cylinder154. Through the fitting 162high pressure air is admitted into thecylinder 154 to displace the piston in a downward direction as viewed inFig. 3 to rotate the sleeve 134. In the lower end, Fig. 3, of thecylinder 154 is threaded a fitting 168 to which is connected an air line170 which communicates with a constant pressure source of compressedair. Also threaded in the cylinder 154 is a fitting 172 which is in theform of a T connection having one end connected to the fitting 129 inthe presser foot cylinder 126 by means of the line 128. The other branchof the T is connected to the fitting 146 by means of the conduit 150.The piston 152 and consequently the sleeve 134 are normally maintainedby air pressure acting against the head 158 in the positions shown inFigs. 3 and 4 with the slot 144 in the sleeve facing the receiving area132. The presser foot 120 is held downwardly by the spring 122 againstthe heads of fasteners located on the sloped portion 130 of the. raceway14. When a blast of air is admitted through the fitting 162 to the upperend of the cylinder 154, as seen in Fig. 3, the piston 152 movesdownwardly, the head 156, being of greater diameter than the head 158,displacing the rack 140 which causes the sleeve to be rotated to aposition wherein the slot 144. faces the air inlet fitting 146 and theclosed wall faces the receiving area 132. The piston head 158 movestoward the cap 161 permitting the pressurized air in the line 170 toflow into the lower end of the cylinder 154, past the necked area 160and into the T fitting 172. A portion of this air passes through theconduit 128 into the cylinder 126 and elevates the presser foot 120,permitting the endmost fastener to fall onto the receiving area 132 withits shank against the then closed wall of the sleeve 134. Anotherportion of the air also passes from the T fitting 172 through the line150 and enters the sleeve 134 through the slot 144 which has becomealined with the fitting 146. The fastener which entered the sleeve andfellinto the conduit 36 during the preceding operating cycle ispropelled by this air blast to the inserting tool.

Upon the release of pressure in the fitting 162 the piston 152 isreturned to its upper position as seen in Fig. 3 by the air pressure onthe lower face of the head 158, the air above the piston head 156escaping through a bleeder valve 186 (Figs. 5 and 6). The pressure inthe line 128 is reduced and the presser foot 120 descends under theforce of the spring 122 into engagement with the heads of fastenerslocated on the sloped area 130. The sleeve 134 is rotated whereby itsslot 144 again faces the receiving area 132 and the fastener thenlocated thereon falls through the slot 144 downwardly into the conduit36 coming to rest at a bend therein ready to be propelled to theinserting gun during'the next operating cycles It will be;noted that theabove described Mcllvin feeding mechanism is operated by a blast of airentering the cylinder 154 through a fitting 162 and by the constantpressure in the line 170, no other operating mechanis being required.

The more common portable pneumatic inserting devices may be classifiedin two general categories, 1)

those in which the actual fastener driving operation is substantiallyinstantaneous, for example, a single-blow.

nail or tack driver, and (2) those in which the driving operationrequires a somewhat longer or sustained period of time, for example,multiple-blow nail drivers and rotary screw drivers. Feeding mechanismsused with the tools in the first category may deliver the next fastenerimmediately upon the 'tool being fired since the tools driving periodsare sufiiciently short so as to be completed before the next fastenercan be propelled through the delivery conduit thereby substantiallyeliminating the possibility of avjam at the tool. However, with tools ofthe second category having longer or sustained driving periods, theactual feeding of a subsequent fastener must be delayed until thedriving operation ceases otherwise a jam will occur at the insertingtool.

a The operation of the fastener inserting device employing applicantsflow responsive valve 38 for supplying fasteners to'tools having asustained driving period, herein illustrated as a pneumatically operatedrotary screw driver, will now be described with reference "to Fig. 6.The screw driver 188 is of a well-known commercial type, not shown indetail, in which a screw is rotatably driven by means of a pneumaticmotor actuated by a trigger 182. The compressed air for operating thegun comes from the line 76 which is attached to the fitting 74 threadedin the casing 40 of the flow responsive valve 38. The line which isattached to the fitting 98 in the flow responsive valve is connected toan air accumulator 184 which is part of the feeder-separator or feedingmechanism. The line 68 which is attached to the fitting66 in the flowresponsive valve is connected to a constant pressuresource of compressedair. The combination of lines- 68 and 76 through which air flows to theinserting tool mayalso be referred to as thefirst line for the purposeof this invention. The line 106 which is attached to the, fitting 104 ofthe flow responsive valve is attached to the upper end of the cylinder154 by means of the 7 fitting 162. The lines 100 and 106 may beconsidered the second line for the purposm of this invention.

When the trigger 182 of the screw driver 180 is depressed, air flowsthrough the line 76 to operate the screw driver. This flow, as statedabove, causes the piston 44 of the flow responsive valve 38 to move tothe left wherein the control or spool valve 60 is moved to a positionwherein the pressurized air in the main chamber 70 may flow by means ofthe passageway 92, through the line 100 into the air accumulator 184.During this time, the air within the line 106 connected to the cylinder154 of the feeder-separator remains at atmospheric pressure and thefeeder-separator is not actuated. Releasing the trigger 182 of the screwdriver after a screw has been driven cuts off the flow of air throughthe line 76 permitting the air in the chamber 72 again to reach the samepressure as that in the main chamber 70, the piston 44 and the spoolvalve 60 again moving to their right-hand positions. At this time, theline 100 is placed in communication with the line 106 by means of thepassageway 110 and the compressed air within the accumulator 184 flowsinto the line 106. The pressurized air in the line 106 upon reaching thecylinder 154 of the separating and feeding element 34 displaces thepiston 152 to actuate the element 34 in the manner described brieflyabove and in more detail in the above-mentioned McIlvin et al.application, whereby a fastener is propelled through the conduit36 tothe screw driver.

An alternative method of supplying fasteners to a substantiallyinstantaneously operated inserting tool illustrated as a single-blownail driver will now be described with reference to Fig. 5. Theinserting gun 188 illustrated in Fig. is identical with that disclosedin an application for United States Letters Patent Serial No. 535,365,filed September 20, 1955, in the names of Fred F. Chellis et al. Withoutdescribing the gun in detail it is suflicient to say that a nail isdriven from the nosepiece 190 thereof when the gun is pressed against awork piece. The gun is operated pneumatically, being connected to theline 76 leading from the flow responsive valve 38. In the same manner asthe screw driver, the operation of the gun 188 causes a flow through theline 76 but because the driving operation is almost instantaneous it isunnecessary to delay the feeding of the next fastener. Accordingly, itis not necessary to employ an air accumulator as part of the feedingmechanism, such as the accumulator 184 illustrated in Fig. 6. The line100, now alone considered the second line, is connected directly to thecylinder 154 and the fitting 104 threaded in the flow responsive valvecasing 40 is replaced by a plug 192. Accordingly, when the piston 44 ofthe flow responsive valve is displaced by the pressure in the mainchamber 70, compressed air flows through the passageway 92 into the line100 directly to the cylinder 154 of the feeding element 34 causing it tooperate immediately as above described. Upon release of the nail drivinggun 188 from the work piece, its nosepiece 190 is returned to itsoriginal position as explained in the above-mentioned Chellis et al.application and the line 76 again reaches full line pressure, the piston44 of the flow responsive valve returning to its right-hand position asshown in Figs. 2 and 5, ready for another operating cycle.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

l. A fastener inserting device having, in combination, a fluid operateddriving tool, a line connected to the driving tool for supplyingoperating fluid thereto, means for feeding fasteners to said drivingtool, and means in said line operative in response to the flow of fluidtherethrough for controlling the operation of said feeding means.

2. A fastener inserting device having, in combination, a fluid operateddriving tool, a line connected to the driving tool for supplyingoperating fluid thereto, means for feeding fasteners to said drivingtool, and fluid responsive means in said line forcausing operation ofsaid feeding means in timed relation to the operation of said drivingtool.

3. A fastener inserting device having, in combination, a fluid operateddriving tool, a line connected to the driving tool for supplyingoperating fluid thereto, means for feeding fasteners to said drivingtool, a member interposed in said line movable from a first position toa second position in response to flow of fluid through said line, meansacting on said member to maintain it in the first position when there isno flow through said line, and means controlled by the movement of saidmember for causing operation of said feeding means in timed relation tothe operation of said driving tool.

4. A fastener inserting device having, in combination, a fluid operateddriving tool, a line connected to the driving tool for supplyingoperating fluid thereto, fluid pressure means for feeding fasteners tosaid driving tool, a valve for controlling the operation of said fluidpressure means, and flow responsive means in said line for moving saidvalve to operate said fluid pressure means in timed relation to theoperation of said driving tool.

5. A fastener inserting device having; in combination, a fluid operateddriving tool, a line connected to the driving tool for supplyingoperating fluid thereto, means for feeding fasteners to the drivingtool, a flow responsive valve interposed in said line, a piston in saidvalve movable from a first to a second position in response to flow offluid through said line, resilient means acting on said piston tomaintain it in the first position when there is no flow through saidline, and means controlled by the movement of said piston for causingoperation of said feeding means in timed relation to the operation ofsaid driving tool.

6. A fastener inserting device having, in combination, a fluid operateddriving tool, fluid pressure means for feeding fasteners to the drivingtool, a flow responsive valve, a first line connecting said valve to thedriving tool for supplying operating fluid thereto, a second lineconnecting said valve to the feeding means for supplying operating fluidthereto, a supply line connecting said valve to a source of pressurizedfluid, a chamber within said valve communicating with the supply line, apiston within said valve movable in response to a flow of fluid fromsaid chamber through the first line, and a control member movable withsaid piston to permit fluid to flow from said chamber through the secondline to the feeding means only when flow takes place from the chamberthrough the first line.

7. A fastener inserting device having, in combination, a fluid operateddriving tool, fluid pressure means for feeding fasteners to the drivingtool, a flow responsive valve, 2. first line connecting said valve tothe driving tool for supplying operating fluid thereto, a second lineconnecting said valve to the feeding means for supplying operating fluidthereto, a supply line connecting said valve to a source of pressurizedfluid, a chamber within said valve in open communication with the supplyline, a piston within said valve movable in response to a flow of fluidfrom said chamber to the first line, a passageway from said chamber tothe second line, and means for controlling flow of fluid through saidpassageway, said means for controlling being movable with said piston topermit fluid to flow from said chamber through the second line to thefeeding means only when flow takes place from the chamber through thefirst line.

8. A fastener inserting device having, in combination, a fluid operateddriving tool, fluid pressure means for feeding fasteners to the drivingtool, said feeding means comprising a fastener handling mechanism and afluid accumulator, a flow responsive valve, a first line connecting saidvalve to the driving tool for supplying operating fluid thereto, asecond line passing through said valve and. connecting the fastenerhandling mechanism to the fluid accumulator, a supply line connectingsaid valve to a source of pressurized fluid, a chamber within said valvein open communication with the supply line, a piston within said valvemovable in response to a flow of fluid from said chamber to said firstline, and a control member movable with said piston to permit fluid toflow from said chamber through said second line to the accumulator onlywhen flow takes place from said chamber to said first line and to permitfluid in the accumulator to flow through said second line to thefastener handling mechanism only after the flow from said chamber to thefirst line terminates.

9. A fastener'inserting device having, in combination, a fluid operateddriving tool, a fluid pressure means for feeding fasteners to thedriving tool, said feeding means comprising a fastener handlingmechanism and a fluid accumulator, a flow responsive valve, a first lineconnecting said valve to the driving tool for supplying operating fluidthereto, a second line passing through said valve and connecting thefastener handling mechanism to the fluid accumulator, a supply lineconnecting said valve to a source of pressurized fluid, a chamber withinsaid valve in open communication with the supply line, a piston withinsaid valve movable in response to a flow of fluid from said chamber tosaid first line, a passageway from said chamber to the second line and aspool valve for controlling flow of fluid through said passageway andthrough said second line, said spool valve being movable with the pistonto permit fluid to flow from said chamber through said second line tothe accumulator only when flow takes place from said chamber to thefirst line and to permit fluid in the accumulator to flow through saidsecond line to the fastener handling mechanism only after the flow fromsaid chamber to said first line terminates,

10. A flow responsive valve comprising a valve casing having an inletopening adapted to be connected to a source of pressurized fluid andfirst and second exit openings, the first exit opening being at alltimes in communication with the inlet opening, means normallyrestricting the flow of fluid from the inlet opening to the first exitopening comprising a piston having a restricted passageway therethrough,means normally maintaining said piston in a position in which fluid mustpass through said restricted passageway to the first exit opening, meansresponsive to movement of said piston for permitting direct flow fromthe inlet opening to the first exit opening, one face of said pistonbeing exposed to the pressure of the fluid at said inlet opening and theother face being exposed to the pressure of the fluid at said first exitopening, said piston being movable in a direction to permit direct flowfrom the inlet opening to the first exit opening in response to a dropin pressure on the face exposed to the first exit opening occasioned bya flow of fluid through said first exit opening, valve means movablewith said piston for controlling the flow of fluid through said secondexit opening, and means to permit limited relative movement between thepiston and said valve means whereby only a substantial movement of thepiston results in movement of said valve means.

References Cited in the file of this patent UNITED STATES PATENTS984,510 Currie Feb. 14, 1911 1,885,363 Leitner Nov. 1, 1932 2,086,236Peo July 6, 1937 2,732,554 Knott Jan. 31, 19 56

